2019-10-17 11:11:24 +03:00
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// This program displays the fibonacci sequence
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2021-12-08 11:09:10 +03:00
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import os
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2019-10-17 11:11:24 +03:00
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fn main() {
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// Check for user input
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2021-12-08 11:09:10 +03:00
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if os.args.len != 2 {
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println('usage: fibonacci [rank]')
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2019-10-17 11:11:24 +03:00
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2021-12-08 11:09:10 +03:00
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return
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}
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2021-02-23 20:43:44 +03:00
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2019-10-17 11:11:24 +03:00
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// Parse first argument and cast it to int
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2021-12-08 11:09:10 +03:00
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stop := os.args[1].int()
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2019-10-30 14:54:38 +03:00
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// Can only calculate correctly until rank 92
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if stop > 92 {
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println('rank must be 92 or less')
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return
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}
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2019-10-17 11:11:24 +03:00
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// Three consecutive terms of the sequence
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2021-12-08 11:09:10 +03:00
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mut a := i64(0)
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mut b := i64(0)
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mut c := i64(1)
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2021-04-20 17:16:35 +03:00
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println(a + c + c)
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2021-02-23 20:43:44 +03:00
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for _ in 0 .. stop {
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2019-10-17 11:11:24 +03:00
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// Set a and b to the next term
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a = b
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b = c
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// Compute the new term
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c = a + b
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// Print the new term
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println(c)
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}
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}
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